Explaining Science – Gene flow among song dialects

Today Kandace Glanville, an OSU Forestry Fisheries & Wildlife major and student assistant in the Borror Laboratory of Bioacoustics, talks with Angelika Nelson, Curator of the Borror Lab, about a recent research publication in the journal Ethology. The study is entitled “High levels of gene flow among song dialect populations of the Puget Sound white-crowned sparrow”.

Find out why we studied the White-crowned Sparrow Zonotrichia leucophrys pugetensis to investigate gene flow among song dialects:

The research aimed to investigate a correlation between behavioral and genetic differentiation:

Our research built on knowledge from previous studies and used samples that were collected previously:

We found gene flow among bird populations that differ in song dialects; this may demonstrate dispersal of young birds across dialect borders:

Our findings are consistent with most studies to date of song and population structure within songbirds. The processes of song learning and dispersal mean that vocalizations are free to vary independently of patterns of divergence in neutral genetic markers.

Reference:
Poesel, Angelika, Anthony C. Fries, Lisa Miller, H. Lisle Gibbs, Jill A. Soha, and Douglas A. Nelson. “High levels of gene flow among song dialect populations of the Puget Sound white‐crowned sparrow.” Ethology 123, no. 9 (2017): 581-592.

 

About the Author: Angelika Nelson is the curator of the Borror Laboratory of Bioacoustics and the social media manager for the Museum of Biodiversity.

A gull look-alike

Another seabird species that I found to breed in Ireland is the Northern Fulmar Fulmarus glacialis. In a fleeting glimpse this bird may look like a gull but a closer look quickly reveals that is a close relative of albatrosses and shearwaters, the tubenoses Procellariiformes.

Can you see how this group of birds, the tubnoses, got its name? Doesn’t it look like they have a tube on top of their bill? This tubular nasal passage is used for olfaction. Yes, some birds do have the ability to smell. Especially seabirds use this sense to locate flocks of krill, shrimp-like animals that feed on single-celled marine plants (phytoplankton) right below the ocean’s surface. Breaking up phytoplankton cells releases a chemical called dimethylsulfide that concentrates in the air above areas where phytoplankton and thus krill are abundant. Researchers suspect that seabirds may smell their prey.

An acute sense of smell may also aid these birds to locate their nest within a breeding colony – you may recall the dense breeding conditions on the coastal cliffs from Monday’s post.

Furthermore, at the base of their bill these true seabirds have a gland that helps them excrete excess salt as they drink seawater. These birds and their relatives often spend long times out over the ocean without any land in sight. Thus they depend on drinking seawater.

So what do Northern Fulmars sound like? They are especially vocal when they return to their partner on the nest, they engage in an often minutes-lasting greeting ceremony. Listen to this pair recorded by Gabriel Leite in Clare county, Ireland (XC372370):

The unique morphological characteristics make these birds well adapted to their preferred environment of the northern oceans. They are among the longest-lived birds known, researchers estimate an average lifespan of 32 years for the Northern Fulmar.

About the Author: Angelika Nelson is the curator of the Borror Laboratory of Bioacoustics and currently teaches at the Audubon summer camp on Hog Island, ME.

 

Songs on both sides of the Atlantic

Like every year I will leave for Hog Island, Maine tomorrow morning. I will teach at two of the Audubon summer camps that have been held on the island almost every summer since 1936. You may recall this from my previous post.

This year I am particularly excited to watch birds along the Atlantic coast as I just returned from a trip to Ireland, on the other side of the Atlantic ocean. There I spotted birds of several species that also occur along the US coast. I doubt that the birds themselves make the crossing, but members of their species reside and breed on both sides of the Atlantic.

Rathlin Island

So which birds are we talking about? In Europe we visited Rathlin island, a small island off the coast of Northern Ireland, where we watched Atlantic Puffins Fratercula arctica, Razorbills Alca torda and Common Murres Uria aalge – or Common Guillemot as they are referred to in the UK. The Royal Society for the Protection of Birds (RSPB) runs a seabird center along the cliffs of the island where volunteers and staff regularly survey the breeding colonies and answer visitors’ questions. The resident naturalist shared with us the latest numbers: they estimate 100,000 Common Murres to breed on the cliffs, with them 20,000 Razorbills and some 700 pairs of Atlantic Puffins, everyone’s favorite due to their colorful breeding plumage.

Two Atlantic Puffins on Eastern Egg Rock

Atlantic Puffin on Eastern Egg Rock

On the US side of the Atlantic, in Maine, some 550 breeding pairs of these colorful seabirds have been reported in the largest colony on Seal island, ME.

Enjoy some photos of the Irish coastal scenery – I wish my photos conveyed the noise and smell that comes with large seabird colonies like these … David Attenborough in his Life of Birds series refers to these breeding conditions as the” slums in the bird world”.

This slideshow requires JavaScript.

Most of these seabirds are not known for their vocalizations (although Black Guillemots may be exceptional with their distinct whistle; you can hear some in the background of the puffin recording below). Here are some recordings that I found in our collection:

Doug Nelson recorded this Atlantic Puffin on Matinicus Rock, Knox county, Maine, USA on 3 June 1981 (BLB23883):

Lang Elliott recorded a Common Murre on water near the Gaspesie Provincial Park, Bonaventure Island, Quebec, Canada on 1 July 1989 (BLB17181):

Common Eider is another bird that breeds on both sides of the Atlantic. Hear some nestling calls recorded by Don Borror on Eastern Egg Rock, Muscongus Bay, Knox county, Maine, USA on 23 June 1958 (BLB3508):

As you can see, most of these recordings were made a long time ago; time to go back and get some more recent recordings!

About the Author: Angelika Nelson is the curator of the Borror Laboratory of Bioacoustics and team-teaches at the Audubon summer camp on Hog Island, ME.

Songsters on the move

I have been teaching a class on Ohio Birds since January during which we visit various field sites around Columbus to look for birds. One main goal is for students to be able to identify birds visually and acoustically by the end of the semester. As you may imagine the birds we have been seeing over this time period have  changed quite a bit.

Not only the species have changed but also overall diversity. Venture out in January and you can call it a good day when you see 15-20 bird species. You want to choose your birding location carefully, a variety of habitats (lake, woodlot, open field, and bird feeder) will increase your numbers. These days however 30 species are the norm, it is migration season! While most of our winter guests such as Dark-eyed Junco and American Tree Sparrow have left us and gone north to their breeding grounds in Canada, many other species that spent the winter south, some as far as Argentina, are on their way to our temperate region.

Blue-gray Gnatcatcher. Photo by Christopher Collins, 2017

Blue-gray Gnatcatcher. Photo by Christopher Collins, 2017, via www.fb.com/roguebirders

Have you seen a Blue-gray Gnatcatcher yet? Guess what this bird feeds on! Listen for their begging-like calls high in the tree tops. Their long tail and light-gray appearance are a good give-away.

Spectrogram of calls of Blue-gray Gnatcatcher

Spectrogram of calls of Blue-gray Gnatcatcher, BLB28872

 

Similarly flitting around in the tree tops are kinglets (family Regulidae). These tiny birds (even smaller than chickadees! they weigh only 10g or 2 nickels) seem to be constantly on the move. One of the two species that can be added to your Ohio list, the Golden-crowned Kinglet, even spends the winter with us. Truly an amazing feat in temperatures that can drop to zero Fahrenheit and below on occasions. A good photo of this species shows off their flashy bright yellow crest bordered by a black eyebrow stripe on each side.

My favorite though is the Ruby-crowned Kinglet, in particular because of its song. It starts out like its close-relative the Golden-crowned with some very high-pitched tsee notes, but then truly distinguishes itself through a jumble of notes, a musical twitter, that seems incredibly loud given the small size of this songster.

Spectrogram of song of Golden-crowned Kinglet

Spectrogram of song of Golden-crowned Kinglet, BLB17541

Spectrogram of song of Ruby-crowned Kinglet

Spectrogram of song of Ruby-crowned Kinglet, BLB11487

 

But do not underestimate the small! My all-time favorite, the Winter Wren, delivers the loudest song (per unit body weight) of all birds, a beautiful cascade of bubbly notes.

Winter Wren. Photo by Christopher Collins, 2016

Winter Wren. Photo by Christopher Collins, 2016, via www.fb.com/roguebirders

While you may get lucky to hear this song in Ohio on occasion from one of the male Winter Wrens passing through, their song is commonly heard in the deciduous and evergreen forests of the north. By the way, did you know that the male hormone testosterone greatly influences bird song? As these males migrate and get ready for the breeding season, their testosterone levels increase and they start practicing their song – even though they are not setting up territories here or trying to attract females.

Spectrogram of song of Winter Wren

Spectrogram of song of Winter Wren, BLB44620

 

There are many ways to appreciate our songbirds. Since I am fascinated by their song I like to record their vocalizations and take these recordings back to our sound lab and look at them. We humans are just so visually oriented that even the song of a Winter Wren may look more beautiful to us than listening to its sound (This is of course not true if you have a musical ear or train yourself to listen carefully and pick out intricate details).

If you are interested in learning how to record bird songs, look at them at home and compare them to each other join me for a Sound Analysis workshop at the nature center at Battelle Darby Creek metro park on Saturday April 29 from 10:30-11:30 am. If you are an early riser, join us on a Bird Walk at 8 am that same day and listen to the bounty of birds singing at this time of the year.

Credits:
Sound descriptions based on the ones given by the Cornell Lab of Ornithology, All about Birds.

Thank you Christopher Collins and Jim McCormac for the bird photos.

All recordings are archived in the Borror Laboratory of Bioacoustics. More detailed information for each can be accessed online; just click on each species’ name:
Blue-gray GnatcatcherGolden-crowned KingletRuby-crowned KingletWinter Wren

About the Author: Angelika Nelson is curator of the Borror Laboratory of Bioacoustics and instructor of Ohio Birds each spring.

*** Which birds are your favorites? ***

 

St Patrick’s specimens

Since it is St. Patrick’s day today I felt inspired to search our collections for specimens from Ireland. None of the sound recordings in the Borror lab were made in Ireland – I hope to change this soon as I am planning a trip to Ireland this May. I will keep you updated on which birds I manage to record. May should be prime singing time for most songbirds as they defend their territory and/or attract a mate.

When I searched the Tetrapods collection I came across some bird eggs that sure enough had been collected from nests in Ireland and transported across the Atlantic ocean to be included in our large egg collection. The majority of the 11 egg sets were accessioned when we received the large egg collection put together by Dr. B.R. Bales. He may not have collected all eggs himself, some of the eggs may have been traded with other egg collectors around the world. Such trades were common in former days. The eggs date back to the early 1900s (1899-1923) as you can see from the labels with each one. To my disappointment none were collected on St. Patrick’s day, but I guess March is a bit early for expecting breeding birds in Ireland!

So which species do these Irish eggs belong to? Take a look at the photos.

This slideshow requires JavaScript.

Only one species is a songbird, the Dunnock. It builds its nest low in a bush and lays 3-5 blue eggs. Under low light conditions, like inside a bush, these eggs are hard to detect by a potential predator. Keep this in mind when you look at the color and markings of the following eggs of seabirds: The Atlantic Puffin digs a burrow in which it lays its single egg. No color camouflage needed there. Similarly the Manx Shearwater digs a 3-6 feet long burrow in which it lays its single egg. Again the white coloration of the egg is a sign of no camouflage needed. The European Storm Petrel places its nest in crevices between or under rocks, or burrows in the soil. Guess the color of its egg … These eggs are actually from two different females because each lays only a single egg per nesting season. Now look at the egg of the Common Murre, do you think this one is well hidden in a burrow or crevice? The intense markings all over the surface camouflage this egg very well against the bare rock it is laid on. The nest site is on cliff ledges or on flat stony surfaces near water. The last set of eggs is from a single female Corn Crake, a bird in the rail family, which builds its nest in grassland and relies on marking camouflage of its 6-14 eggs per clutch.

Bird eggs, their colors and markings are fascinating and have inspired many research studies. Do you have any burning questions? Leave a comment and we will get back to you.

Have you ever seen any of these birds? The seabirds can be found on both sides of the Atlantic. I have seen Atlantic Puffins on a puffin cruise off the coast of Maine.

About the Author: Angelika Nelson is curator of the Borror Laboratory of Bioacoustics and former curator of the OSU Tetrapods collection.

 

*** We would like to hear from you, please leave a comment ***